If you don't want to use rubber bands to hold your cards together, these clear card cases will help solve the problem, these boxes protect and organize your cards by holding them in place, and allowing them to stack on top of each other.
It is 350 TIMES MORE RESISTANT to the diffusion of gases like oxygen, carbon dioxide, sulfur dioxide, etc. than poly bags. Resealable bags resistance to moisture, insect attack, fungus, mold, mildew, acid, oils, grease, and solvents is excellent. Mylar is the Infinity Gauntlet of storage bags.